1. Field of the Invention
The present invention relates to a printed circuit board design system, and in particular to a printed circuit board design system for performing, with a three-dimensional (3D)-CAD system, a mounting design including a cabinet.
2. Description of the Related Art
In recent electronic equipment such as mobile terminal equipment, not only the downsizing/complication of its shape but also the reduction of its TTM (Time To Market) has been demanded. With this demand, its printed circuit board has been downsized/complicated, so that accuracy of outer dimensions, which is required for removing an interference with a cabinet, and besides reduction of mounting design man-hours have been demanded.
A prior art printed circuit board design system completes the arrangement of mounting components (parts) on a printed board, and then generates a 3D (three-dimensional) model (data) of a printed circuit board unit. Based on this model, a 3D-CAD (Computer-Aided Design) system has determined whether or not the printed circuit board and the cabinet interfere with each other.
FIG. 15 shows an arrangement of a printed circuit board design system (hereinafter occasionally abbreviated as PCB-CAD system) 10 and a 3D-CAD system 30.
The PCB-CAD system 10 is composed of a PCB mounting design DB (Data Base) storage 11 and a 3D converter 13 which inputs PCB information stored in the PCB mounting design DB storage 11 and 3D component LIB (Library) information from the 3D-CAD system 30 to provide a 3D model of the printed circuit board to the 3D-CAD system 30.
The 3D-CAD system 30 is composed of a 3D model storage 31 for storing the 3D model of the printed circuit board, a cabinet interference inspecting portion 34 for inspecting a cabinet interference based on model information stored in the 3D model storage 31, a 3D component LIB storage 33 for storing the 3D component library information, and a manual input portion 35 for inputting data of the components in the 3D component LIB storage 33 based on a management sheet 36.
FIG. 16 shows a prior art procedure example for preparing a 3D model of a printed circuit board.
The PCB-CAD system 10 firstly arranges the components on the printed board to perform the mounting design of the printed circuit board (at step S70 in FIG. 16), which is repeated until the component arrangement is completed (at step S71).
When the component arrangement is completed, the 3D converter 13 converts the printed circuit board into the 3D model to be sent to the 3D-CAD system 30 (at step S72).
In the 3D-CAD system 30, the 3D model storage 31 stores the 3D model received, while the cabinet interference inspecting portion 34 inspects the interference between the 3D model and the cabinet (at step S73).
When the components are required to be moved because of a contact between the printed circuit board and the cabinet, or a dimensional shortage, the procedure returns to step S70 to execute a rearrangement of the components (at step S74). Hereafter, the same procedures are repeated until the component move becomes unnecessary. When the move is not required, a wiring/design rule check (DRC) of the printed circuit board is performed to complete the operation (at step S75).
The components mounted on the printed board comprise ones required to be arranged on fixed positions (hereinafter occasionally referred to as fixed components), and ones whose arranged positions can be moved (hereinafter occasionally referred to as nonfixed (unfixed) components).
FIG. 17 shows a procedure in case where both fixed and nonfixed components are included in the procedure of the 3D model preparation shown in FIG. 16.
The PCB-CAD system 10 performs the mounting design of the printed circuit board 50 which mounts thereon a fixed component I4, and nonfixed components I5 and I6 on a printed board 51. The 3D converter 13 converts the printed circuit board 50 into the 3D model to be sent to the 3D-CAD system 30.
In the 3D-CAD system 30, the cabinet interference inspecting portion 34 performs the interference inspection between the received 3D model and the cabinet. In the presence of the interference, the component is required to be moved or the dimensions of the cabinet to be changed in order to avoid the interference. However, fixed/nonfixed states of the components I4-I6 can not be recognized by the 3D models.
Therefore, in order to recognize the fixed component on the 3D-CAD system 30 before the interference inspection, the color of the fixed component was changed.
FIG. 18 shows a 3D model of a mechanical component mounted on the printed board 51.
The 3D converter 13 firstly converts a mechanical component E1 of a complicated shape into the maximum rectangle E, and then makes a rectangular parallelepiped, which has the rectangle E as a base and the maximum height H of the component E1, a pseudo 3D model of the mechanical component E1.
In 3D modeling by such a prior art PCB-CAD system, there is a possibility that man-hours increase and manual mistakes occur as follows:
{circle around (1)} The 3D model conversion was not performed before completing the arrangement of the mounting component in the printed circuit board 50.
{circle around (2)} When the change of the component shape occurred in the PCB-CAD system 10, the component shape at the library in the 3D-CAD system 30 was correspondingly changed by the manual input portion 35. For this reason, data for identical components stored in the PCB mounting design DB storage 11 and the 3D component LIB storage 33 were occasionally different from each other.
Also, in the 3D-CAD system 30, whether or not the 3D model of the component in the printed circuit board 50 is the 3D component model of the 3D component LIB was visually recognized.
{circle around (3)} In the printed circuit board mounting design, the attributes of the components; an arranged component/unarranged component, a fixed component/nonfixed component, a manufactured height (rise) by soldering, a pseudo component (switching land or the like) were not taken into consideration, so that they could not be recognized.
Therefore, the component models in which the display color is changed in order to recognize the fixed component/unarranged component on the 3D-CAD system 30 and the manufactured height is taken into consideration were prepared before the interference inspection.
{circle around (4)} The mechanical component or the like was modeled by the maximum rectangular shape, so that the inspection of the cabinet interference was inaccurate, leading to an occurrence of interference which does not inherently exist. Therefore, the accurate shape of the mechanical component was provided from the manual input portion 35 of the 3D-CAD system 30.
It is accordingly an object of the present invention to provide a printed circuit board design system generating a 3D model of a printed circuit board which mounts thereon a component on a printed board, performing, with a 3D-CAD system, a mounting design including a cabinet, and generating an accurate 3D model of the printed circuit board to be provided to the 3D-CAD system.
In order to achieve the above-mentioned object, the printed circuit board design system according to the present invention comprises: a converter for converting the printed circuit board into one or more models based on attributes preliminarily added to the component.
Namely, the converter can disassemble the printed circuit board into one or more constitutional elements according to the attributes preliminarily added to the component, and convert the constitutional elements into the models.
Thus, the printed circuit board can be disassembled into a plurality of portions corresponding to the attributes of the mounting component to perform a modeling, so that accurate modeling can be done without mistakes in less man-hours depending on design stages of the printed circuit board.
Also, in the present invention, when the attribute is a mounting side, the above-mentioned converter may convert the printed board and a component mounted on an L1 side into an L1 side portion model, and may convert the printed board and a component mounted on an Ln side into an Ln side portion model.
Namely, the converter can divide the printed circuit board into the model composed of the printed board and the component mounted on the L1 side (surface), and the model composed of the printed board and the component mounted on the Ln side (underside) to be generated.
Thus, the L1 side portion model and the Ln side portion model are merged by the common printed board, thereby enabling the model of the printed circuit board to be prepared and enabling the man-hours to be reduced in comparison with the case where a printed circuit board unit is modeled.
Also, in the present invention, when the attribute is one of an arrangement and a fixation, the above-mentioned converter may convert the component which is not arranged on the printed circuit board into an unarranged component model, and may convert the component which is not fixed into a nonfixed component model.
Namely, the converter converts the component which is not arranged on the printed board into the unarranged component model which can be recognized to be not arranged as the model, and generates the nonfixed component model which can be recognized to be not fixed as the model of the component not fixed on the printed board.
Thus, the 3D-CAD system can recognize whether or not the mounting component is already arranged or fixed on the printed board, and can verify the propriety of the position by moving the position of the component which is not yet arranged or fixed on the 3D-CAD system depending on the design stages.
Also, in the present invention, the above-mentioned converter may convert the printed board and the component into a library model related to the attribute.
Namely, the converter can convert the printed board and the component mounted thereon into the models, and make the models in the form of a library based on the attributes.
Based on the library, the arrangement of the mounting component and the like can be studied by using the 3D-CAD system.
Also, in the present invention, the above-mentioned converter may convert the component into either a pseudo shape model or a detailed shape model.
Namely, the converter can generate a model of e.g. an electronic component in the components mounted on the printed board by a simplified pseudo shape model of a rectangular parallelepiped, a cylinder, or the like, and can prepare a model of a mechanical component by an accurate detailed shape model.
Thus, the printed circuit board can be modeled with divided into portions requiring accuracy and portions which can be simplified, thereby enabling the man-hours and the time required for modeling to be reduced.